#!/usr/bin/env python


while True :
    input = raw_input("please input yourname: ")
    if input == 'zhangsan':
        password = raw_input("please inut your password:")
        p = '123456'
        while password != p:
            password = raw_input("Wrong password ,input again: ")
        else:
            print "Success! welcome login!"
            break
    else:
        print "Sorry!!! user %s dosen't exit!" % input

